This all in one product supports CAS 2 5-2-2 at PC3200 400MHz DDR and the extreme CAS 2.5 7-4-4 at PC4400 550MHz DDR! The Ultra-X achieves the most aggressive timing possible on the DDR memory ever! Moreover, random sample testing in GeIL labs shows these sticks are also capable of running with CAS 2.5 5-3-3 at PC4000 500MHz and CAS 2.5 7-4-4 at PC4400 550MHz! These latencies are significantly faster than all existing modules in the DDR memory market available today.